Mega Code Archive
Listening for Changes to a Class
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class Tracker
def important
"This is an important method!"
end
def self.method_added sym
if sym == :important
raise 'The "important" method has been redefined!'
else
puts %{Method "#{sym}" was (re)defined.}
end
end
def self.method_removed sym
if sym == :important
raise 'The "important" method has been removed!'
else
puts %{Method "#{sym}" was removed.}
end
end
def self.method_undefined sym
if sym == :important
raise 'The "important" method has been undefined!'
else
puts %{Method "#{sym}" was removed.}
end
end
end
class Tracker
def new_method
'This is a new method.'
end
end
# Method "new_method" was (re)defined.
class Tracker
undef :important
end
# RuntimeError: The "important" method has been undefined!
class Tracker
include Enumerable
end
# Nothing!
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